The present invention relates to a manufacturing system for producing endless tracks. More specifically, the present invention is directed to a method of manufacturing endless tracks for track driven vehicles such as snow mobiles, earth moving machines, agricultural equipment and the like.
Earthmover machines and agricultural equipment have ground engaging means employing endless tracks driven by drive wheels. The endless track, or belt, is assembled over a plurality of wheels, at least one of which is a drive wheel, and is engaged by the drive wheel. Such track systems are increasingly more common because the tracks have greater traction in soil and cause less ground compaction than conventional pneumatic tires.
Methods for manufacturing reinforced, endless rubber track can be both expensive and time-consuming. Some methods and apparatus used for the manufacture of industrial belts may be applicable to endless vehicle tracks. However, because of the large differences in the sizes of the belts, which typically have a size expressed in inches or cm, and endless rubber track, which typically have sizes expressed in feet, a simple scale-up of belt technology is not always possible and may not yield usable rubber track. This is self evident due to the greater amount of rubber and reinforcement that must be vulcanized for tracks in comparison to belts.
In forming tracks, there are several known methods for forming endless reinforced track. U.S. Pat. Nos. 5,536,464, and 4,207,052 illustrate a few conventional methods.
In these known track forming methods, the track carcass, the various rubber layers and reinforcement means are wound on a fixed circumference drum. The circular carcass is then placed into an open xe2x80x9cCxe2x80x9d press for curing, wherein the first and last heat must match up to create the appearance of an endless built and cured rubber track.
Because of tooling configuration limitations, as the track diameter decreases the number of heats required to cure the entire track increases, increasing the likelihood of uneven cures at the match points of the heats. Additionally, for each different track size there must be a drum capable of forming a carcass of that size, either an expandable or a fixed diameter drum.
The present invention is directed toward a manufacturing system for producing endless tracks. The disclosed method may be used on any size track, and for any core construction. The disclosed method has faster build and cure times than conventional methods, and yields a uniform product comparable to conventionally produced tracks. The system is a more efficient and more flexible manufacturing system capable of high-volumes.
The track produced is a homogeneous construction except at a splice area. The external appearance of the track produced by the disclosed invention is substantially equivalent to the track produced by the conventional methods.
In one aspect of the disclosed invention, a method of manufacturing a cured endless lugged track is disclosed. The lugged track has at least one sheet of curable material, at least one sheet of reinforcement material, and a plurality of lugs to form a lugged rubber track. The method comprising the steps of: a) prior to curing, laying up on a flat build table the at least one sheet of curable material and the at least one sheet of reinforcement material to form an uncured carcass and b) splicing and curing the uncured ends of the carcass to form the endless lugged track.
In another aspect of the invention, only a central portion of the carcass is cured prior to splicing, leaving the opposing ends of the materials uncured. The cured central portion of the carcass has a length of 75 to 95 percent of the total length of the carcass.
In another disclosed invention, there is a method of manufacturing a cured endless lugged track. The method has the following steps: a) laying up a plurality of curable sheets and reinforcement sheets until a desired thickness is achieved, forming a carcass, and b) curing the carcass and adhering a plurality of lugs to the carcass, only a central portion of the carcass is cured. The cured central portion may have a length of 75 to 95 percent of the total length of the carcass.
Also disclosed is a manufacturing system comprising three cells: a building cell, a flat cure press cell, and a splice cure press cell. Each cell is performed in series with the appropriate necessary material handling of the product from one cell to the next cell.
In one aspect of the inventive manufacturing system, the following occurs in each manufacturing cell. In the building cell, a finite length carcass comprising at least one sheet of curable material and at least one sheet of reinforcement material is formed. In the flat cure cell, a central portion of the finite length carcass is cured. In the splice cure press cell, the finite length partially cured carcass is spliced and cured at the splice point to form an endless track.
In another aspect of the invention, the build cell is comprised of at least one material load cartridge, a build table, a build shuttle that travels the length of the build table.
In another aspect of the invention, the flat cure press cell is comprised of a carcass loader, a press for curing the carcass, and an unloader for removing the carcass from the press.